Threadless tube coupling



Dec. 12, 1950 S. GUARNASCHELLI THREADLESS TUBE COUPLING Filed May 16,1947 zzvmvron. fife 1270271 GuarnasdzeZZi BY 9 Q W '00, 2| l2 PatentedDec. 12, 1950 .PATJENT 'OFFIClEI THREADLES'S TUBE COUPLING Stephen:Guarnaschelli, Naugatuck, Conn, as-

.signorto vTheBrcckway Company, Naugatuck,

"Conn a .cor.poration of Connecticut -Application May 16, 1947, SerialNo. 748,399

, .1. Claim. 1

invention relates to pipe fittings and more particularly toself-flaringfittings wherein; the

ductile metal pipeaor' tubing is automatically sfla'red when the fittingis made up.

- It hasbeen thegpractice heretofore :whencouxpling such pipe ?or.tUbiHg-"JtOIEpaI'tS of machines or other apparatus to usesspe'cialtoolsto fprefiare. the'end of thevpipe or assemble variousparts vofthefitting 3-011 the pipebefore making the connection. Thisrequiredconsiderabletime *especially' when many connections. were to be made.Also after the-connections were made up if leaks developed .anewsdttinghad-to :beused with the consequent loss of the first-.fittingused. Thesefittings when once used were, not suitable for re-use because of theirfragile construction or permanent distortion of their parts.

, However the difficulties above referredto have been solvedbyrthe-presentinvention by providing an improved self-flaring fittingwhere the pipe is merely inserted intothe-fitting as far as it will goand'a coupling :member turned to cause the pipe toflare-and be seated inthe fitting to .provide a positive, .leakeproofsconnection.

LAn'object .of this invention is to provide-a selffiaring fittingwherein the force required to make up. the flare fitting is reduced to aminimum.

.Another object is to provide a selfeflaringfitting. where the-danger ofoverewrenching ,is virtually eliminated, unless it be so excessive as topermanently destroy the fitting.

A further object is'to-provide .a self-flaring fitting that iseconomical in useand can be used over and overagain to 'fiare pipe.

These and other objects which will appear below, are accomplishedaccording to'the present invention, byeproviding afittinghaving a bodyhaving a recess anda flare-forming projection within the recess,.'andproviding. a ferrulewhich is split and which when forced. into therecess H squeezes togetherland grips thepipe so that further advancementofthe ferrule carries the pipe forward and causes thepipe to be flaredover the projection. The continued forward .movement of the ferrule.causes the endof the ferrule, which preferably has a beveled seatfitting thelfiared portion to clamp theflared portion between itselfandthe flare-forming. projection .onthebody. .A. draft member havingscrewthreaded engagement with the bodydrives the f erruleinto. the body.Preferably, the draft member and ferrule-have cooperating surfaces whichare substantiallynormal to the. axis of the pipe so that when .the draftmember-is rotatedto advance .the ferrulethere 'isno squeezing action"rule i2.

between 'the draft' member and the ferrule, and resistance to rotationof the draft member is reduced to a minimum.

By having the ferrule split and having it squeezed together solely byits engagement with the walls of the non-rotating body, the effortrequired to clampthe ferrule on the pipe and ultimately fiare thepipeand clamp it to the body is substantially reduced.

Since the ferrule isfsplit and separate from they draft member, shouldthe con'nectiomwhen made-up, prove faulty, :resulting for instance fromimproper positioning ofthe [pipe in the fitting at the start of theopera-tion, the ferrule maybe spread open jbythe use of: a screwdriverslipped beckon the pipe, the unsatisfactory flared seat :cut off and thepipe -may be reflared inthe .male thread and the draft member has thefemale threads.

As-shown in the accompanying drawings, the

fitting of the present invention comprises two coupling members I0 andII and a separate fer- The member it is provided at one .end

with a threaded extension [3 adapted .to be screwed into athreadedorifice of apassage .14 .in supporting structure or other device i5 and-has -a bore i6 communicating with :said passage 14 and extendingthroughthe member to a conical-flare-forming projection 11- at the otherend.

-..The:projection H extends into a cavity [8 of .an enlarged portion L!of the member 13 and hastits conical surface Ha joined by a narrow .wall20,substantially perpendicular to said surface Ha, to a smooth wall 2!which extendsoutwardly beyond-the end of the projection to themouth'of-said cavityand forms therewith an annular recess 22. At the endof the wall 2 the :cavity 18 is provided with-internal threads 23 forcooperating with corresponding threaded portion of .the other. member IThe member .I I comprises-the draft means and has a bore 24 slidablyconforming to the outside diameter of a length of ductile pipe 25 whichis to be coupled to member I0. The member I I has external threads 26adapted to cooperate with the internal threads 23 of the member I and arear portion comprising a nut portion 21 of a hexagonal shape to beengaged by a wrench.

In the form of the invention at present pre ferred the fitting isprovided with the separate ferrule I2 to grip the pipe in making theflared connection. As shown in Figs. 3 and 4 the ferrule 52 comprises acollar or ring 23 split by a longitudinal slot 29 and adapted to haveits bore slidably fitting the pipe 25. The forward end of the ring 28has a conical inner surface 30, corresponding to the taper of thesurface Ila of the conical projection I1. The rear end of the ring 28 isprovided with a flat surface 3I, substantially perpendicular to thelongitudinal axis of the ring and adapted to be engaged by a similarflat surface 32 at the forward end of the member II, for reasons whichwill be later explained.

The members If! and H and the ferrule 28 comprising the fitting areassembled before pipe is inserted in the fitting, the ring 28 beingplaced in the cavity I8 and the member II screwed therein until the flatsurfaces 3i and 32 engage to bring the forward end of the ring intocontact with the mouth of the recess 22. By reason of the fact that thering 28 fits not too loosely in the threaded cavity of the body and thatthe flat surfaces 35 and 32 of the ring 28 engage, the

' ring will always be centered with respect to the longitudinal axis ofthe fitting. Thus the assembly of parts may be made before shipment.

Since the projection ring 23 and the bore 24 are held in alignment inmaking-up the connection the pipe is merely inserted into the fittingthrough the member I I until the forward end of the pipe engages theconical surface ii'a of the projection 57. As the member II is screwedinto the member IE3 the ring 23, having its front contacting edgechamfered at 23a enters and moves into the recess 22. The movement,according to the present invention caused the rings to be squeezedtogether to grip the pipe. For this purpose the wall of the recess 22and the outer surface of the ring are inclined relative to each other toproduce a wedging action. As shown the wall 2I of the recess 22 istapered so that when the ring 28 enters the annular recess 22, theforward edge of the ring 28 is compressed and grips the pipe 25 near itsforward end. Since the ring 28 is separate and free from the member IIthere is no tendency for it to turn and thus twist the pipe 25 duringthis action as the surface 32 will slidably engage the surface 3! on thering 28. After the initial gripping of the pipe 25 by the ring 28,continued rotation of the member I! will force the pipe 25 and ring 28ahead causing the ring 28 to further grip the pipe 25 at the same timethat the end of the pipe is carried forward and forced to flare over theconical projection If. This continues until the forward end of the ring28, and its conical surface 39 corresponding to the taper of the surfaceIla of the projection il, engages the flare 34 and clamps it to theprojection under longitudinal pressure in leak-proof engagement.

The important advantage of this fitting is that the forces holding theflared pipe and the fitting are all longitudinal forces as distinguishedfrom radial or compression forces, for, with the 4 ring 28 and member IIhaving flat engaging surfaces 5 and 32, the forces applied to the ring23 are all axial and thus the ring i not dependent on the pipe 25 tosupport it against collapsmg.

By having the ring 28 split rather than solid it can be made thick andstrong and yet be compressible, for a solid ring to be squeezed againstthe pipe 25 must be thin and relatively weak. With the provision of aheavy ring 28 it is possible to apply considerably more force to theflare without damage to the ring thus providing a more positive andleakproof connection.

The flared pipe may be easily removed for inspection of the flare, ifdesired, by merely unscrewing the member H and pulling the pipe out ofannular recess 22 which has its two surfaces tapered as at Fla and 2ithus facilitating said withdrawal.

The fitting which is made of rugged construction can be used over andover again to flare pipe. After the flared pipe is removed from themember II), if it is to be shortened or a new flare is desired, it ismerely necessary to spring the ring open with a screw driver, slide thering 28 back on the pipe 25, cut off the first flare and then make thenext flare as described above.

The taper in the wall 2| or on the ring 28 acts to bring pipe having alarge internal diameter to the size of the conical projection I7. Thissituation exists when steel pipe is used with a fitting that is intendedfor copper pipe as the internal diameter of the copper pipe is smallerthan for the steel pipe. Also the control of the amount of squeeze onthe pipe may be varied by increasing or decreasing the width of the sloton the ring 28.

As shown in Fig. 5 the draft member may be in the form of a nut I Iawhile the body member is in the form of a plug Ifia, which is thereverse of the arrangement shown in Fig. 2. Nevertheless the operationsof the body and draft member and the ferrule are the same and one formor the other may be used depending on whether the body is to have anexternal or internal threaded surface.

Variations and modifications may be made within the scope of thisinvention and portions of the improvements may be used without others.

I claim:

A pipe connector comprising a body men-lb r having a projection having aflare-forming su face, an axially extending wall surrounding saprojection and with the latter providing a ar receiving recess Ofdeterminate size to the flared pipe and the hereinafter mentio sleeve,said recess extending axially beyond flare-forming surface of theprojection de minate distance dependent upon the amo of pipe to beflared and being tapered anally tc ward the flare-forming surface, adraft I enrber threaded to said body member, an split sleeve joined tothe draft member for advancement therewith, said sleeve having a bore ofgreater diameter than the smallest diameter of said projection to freelypass a pipe therethrough to abut said flare-forming surface of theprojection, said sleeve having an end portion, the outer diameter ofwhich excee s the diameter of the recess so that the end portion of thesleeve engages the tapering wall at the outer end of the recess, wherebythreading of the draft member upon said body causes the sleeve toadvance into said recess to be closed on compressed into clampingengagement with the pipe 5 6 at a place thereon spaced a'dista-nce fromthe Number Name Date pipe end dependentupon said determinate dis-1,755,210 Dohner Apr. 22, 1930 tance to extrude said pipe along thefiare-form- 1,982,533 Parker Nov. 27, 1934 ing surface of the projectionand substantially 2,090, 66 Parker Aug. 17, 1937 fill said recess toform a leak-tight joint with r, 2,112,239 Guarnaschelli Mar. 29, 1938said pipe. 2,271,502 Snyder Jan. 27, 1942 STEPHEN GUARNASCHELLI.2,316,306 Parker Apr. 20, 1943 2,320,812 Cowles June 1, 1943 REFERENCESCITED 2,443,187 Hobb June 15, 1943 The :following references are ofrecord in the l i 2,466,057 SOmma Apr. 15, 1949 file Of this patent:FOREIGN PATENTS UNITED STATES PATENTS Number Country Date Number NameDate 569,953 France Apr. 22, 1924 406,060 Potts July 2, 1389 1.3 97,6 Grat Britain Aug. 31, 1933

